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#2
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It is a truism
On 11/14/2014 3:55 PM, wrote:
Jerry Stuckle wrote: On 11/14/2014 12:34 PM, wrote: Jerry Stuckle wrote: On 11/13/2014 6:12 PM, wrote: FBMboomer wrote: On 11/12/2014 1:50 PM, gareth wrote: It is a truism that short antennae are poor inefficient radiators, and no amount of infantile bluster by Americanoramuses will change that. The truth does not need the violence of abuse to force its way down people's throats. A perfect example is a G5RV on 75 meters. They suck. When someone joins our group rag chew on 75, and they have a poor signal, The first thing I ask is "Are you using a G5RV". We all have a chuckle when they answer yes and then ask how we knew. :-) False logic. You don't know how many people with good signals are using G5RV's, because you only ask those with poor signals. Trying to prove with math that short antennae work as well as say a 1/2 wave dipole may give someone great sport. However, in the real world, short antennae suck big time. I have been an American for most of my life. Please do not paint us all with the same brush. Yes and no. Depending on their design, short antennas can be very efficient. See http://www.futurity.org/radio-wave-c...phones-801322/ for an example. But others are correct. The antenna itself is an efficient radiator; it's the matching network that lowers *antenna system* efficiency. Any dipole type antenna will suck on 75M if mounted less than about 100 feet, or about .4 wavelengths. Below that you are warming clouds. So now it's 100 feet? It used to be 60 feet. But I have proof that is not the case. So do a lot of other hams I know. Your "facts" are for an idealized installation. Reality is much different, and will never get the ideal specifications you claim. For a dipole over average ground: Height Gain @ Elevation lambda 0.1 3.89 90 0.15 5.55 90 0.2 5.95 90 0.25 5.81 62 0.3 5.80 48 0.35 6.00 40 0.4 6.38 35 0.45 6.86 31 0.5 7.41 28 0.55 7.76 25 0.6 7.87 23 0.65 7.76 21 0.7 7.54 20 0.75 7.30 18 0.8 7.16 17 0.85 7.15 16 0.9 7.26 15 0.95 7.47 15 1 7.71 14 At 75M .4 lambda is about 100 feet. Generally for DX a takeoff angle of 30 degrees or less is the rule of thumb for best general performance. Of course the antenna still "works" at other heights, but if DX is what you want to achieve, then best results, on the average over average ground, the antenna will work best for that at a height of .5 lambda or better. Now is you happen to be in a salt water marsh surrounded by 100 foot tall steel blimp hangers, your results may vary. You ignore the fact this is an idealized environment. That is NEVER the case in a real installation. You ignore the fact this is modeled on an AVERAGE environment. But you claim it is an absolute fact that an 80 meter antenna at less than 100' is crap. This is solid proof. I have WAS on 75 SSB (from Iowa) with an inverted Vee. The top was only 50' in the air. And late at night in the wintertime I had pretty solid communications over much of the continental U.S. (back in the late 70's and early 80's). Big whoop. The post wasn't about how many QSL cards have been collected, it was about antenna patterns. And I wouldn't have gotten that coverage with an antenna that was "crap". Antennas NEVER work "as predicted" - and anyone who claims they do does not understand antenna operation. Any prediction is as good as the model used to make the prediction. If one can not build a model that is accurate to about two digit accuracy, then they shouldn't be trying to build models. Then tell my why my antenna regularly had a solid signal if it was "crap"? And BTW - I suspect the vast majority of hams on 80 meters have antennas much lower than your claimed 100' - yet they get out quite well. So much for your "crap". Theory is fine - but only as far as you can apply it to the real world. -- ================== Remove the "x" from my email address Jerry, AI0K ================== |
#3
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It is a truism
Jerry Stuckle wrote:
On 11/14/2014 3:55 PM, wrote: Jerry Stuckle wrote: snip You ignore the fact this is an idealized environment. That is NEVER the case in a real installation. You ignore the fact this is modeled on an AVERAGE environment. But you claim it is an absolute fact that an 80 meter antenna at less than 100' is crap. This is solid proof. I never made any such claim nor did I say "an 80 meter antenna at less than 100' is crap". I posted the NUMBERS for an AVERAGE situation. If you wish to disucss "crap", then first define "crap" in numbers. I have WAS on 75 SSB (from Iowa) with an inverted Vee. The top was only 50' in the air. And late at night in the wintertime I had pretty solid communications over much of the continental U.S. (back in the late 70's and early 80's). Big whoop. The post wasn't about how many QSL cards have been collected, it was about antenna patterns. And I wouldn't have gotten that coverage with an antenna that was "crap". Again, I never said anything was "crap"; that is your word and has no meaning until defined. Antennas NEVER work "as predicted" - and anyone who claims they do does not understand antenna operation. Any prediction is as good as the model used to make the prediction. If one can not build a model that is accurate to about two digit accuracy, then they shouldn't be trying to build models. Then tell my why my antenna regularly had a solid signal if it was "crap"? And BTW - I suspect the vast majority of hams on 80 meters have antennas much lower than your claimed 100' - yet they get out quite well. You really do not undertand things like "optimal", do you? And once again, I never said anything was "crap"; that is your word and has no meaning until defined. So much for your "crap". Theory is fine - but only as far as you can apply it to the real world. Most people do not have a problem with applying theory to the real world, but apparently you do. I couldn't care less. And once again, I never said anything was "crap"; that is your word and has no meaning until defined. -- Jim Pennino |
#4
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It is a truism
On 11/14/2014 4:26 PM, wrote:
Jerry Stuckle wrote: On 11/14/2014 3:55 PM, wrote: Jerry Stuckle wrote: snip You ignore the fact this is an idealized environment. That is NEVER the case in a real installation. You ignore the fact this is modeled on an AVERAGE environment. But you claim it is an absolute fact that an 80 meter antenna at less than 100' is crap. This is solid proof. I never made any such claim nor did I say "an 80 meter antenna at less than 100' is crap". That's true. You said is sucks. Let me quote you: "Any dipole type antenna will suck on 75M if mounted less than about 100 feet, or about .4 wavelengths." I posted the NUMBERS for an AVERAGE situation. And claimed the numbers as an absolute. If you wish to disucss "crap", then first define "crap" in numbers. If you wish to discus "suck", then first define "suck" in numbers. I have WAS on 75 SSB (from Iowa) with an inverted Vee. The top was only 50' in the air. And late at night in the wintertime I had pretty solid communications over much of the continental U.S. (back in the late 70's and early 80's). Big whoop. The post wasn't about how many QSL cards have been collected, it was about antenna patterns. And I wouldn't have gotten that coverage with an antenna that was "crap". Again, I never said anything was "crap"; that is your word and has no meaning until defined. You did say "suck" for any dipole under 60' - I can pull up the post (in another thread) if you wish - but you already denied you said it in that thread, despite the direct quite. Here you said it would "suck". That is YOUR word and has no meaning until defined. Antennas NEVER work "as predicted" - and anyone who claims they do does not understand antenna operation. Any prediction is as good as the model used to make the prediction. If one can not build a model that is accurate to about two digit accuracy, then they shouldn't be trying to build models. Then tell my why my antenna regularly had a solid signal if it was "crap"? And BTW - I suspect the vast majority of hams on 80 meters have antennas much lower than your claimed 100' - yet they get out quite well. You really do not undertand things like "optimal", do you? You really do not understand things like "suck", to you? And once again, I never said anything was "crap"; that is your word and has no meaning until defined. Not in this thread - but you did in another thread. Here you said "suck". So much for your "crap". Theory is fine - but only as far as you can apply it to the real world. Most people do not have a problem with applying theory to the real world, but apparently you do. I couldn't care less. Yes, you really do have a problem with mixing theory and real world. And once again, I never said anything was "crap"; that is your word and has no meaning until defined. Once again, you didn't say "crap" in this thread - you said "suck". But you DID say "crap" in another thread. Do I need to paste THAT quote, also? Until you can prove your "crap" and "suck" theories, you are full of "crap" and your theories "suck". And don't try to quote ideal situations. Look at the REAL WORLD. You neglect that the vast majority of people on 80 meters (including me) use antennas which are less than 100' above the ground - yet we work the band quite well. And our signals are not "crap", nor do they "suck". Now if YOU have a problem with an 80 meter antenna, that's YOUR problem. Not the rest of the world's. -- ================== Remove the "x" from my email address Jerry, AI0K ================== |
#5
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It is a truism
Jerry Stuckle wrote:
On 11/14/2014 4:26 PM, wrote: Jerry Stuckle wrote: On 11/14/2014 3:55 PM, wrote: Jerry Stuckle wrote: snip You ignore the fact this is an idealized environment. That is NEVER the case in a real installation. You ignore the fact this is modeled on an AVERAGE environment. But you claim it is an absolute fact that an 80 meter antenna at less than 100' is crap. This is solid proof. I never made any such claim nor did I say "an 80 meter antenna at less than 100' is crap". That's true. You said is sucks. Let me quote you: "Any dipole type antenna will suck on 75M if mounted less than about 100 feet, or about .4 wavelengths." That was in response to the original poster who said his antenna sucked, not me. I posted the NUMBERS for an AVERAGE situation. And claimed the numbers as an absolute. I never made any such claim. snip remaining repetitive puerile drivel -- Jim Pennino |
#6
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It is a truism
On 11/14/2014 10:02 PM, wrote:
Jerry Stuckle wrote: On 11/14/2014 4:26 PM, wrote: Jerry Stuckle wrote: On 11/14/2014 3:55 PM, wrote: Jerry Stuckle wrote: snip You ignore the fact this is an idealized environment. That is NEVER the case in a real installation. You ignore the fact this is modeled on an AVERAGE environment. But you claim it is an absolute fact that an 80 meter antenna at less than 100' is crap. This is solid proof. I never made any such claim nor did I say "an 80 meter antenna at less than 100' is crap". That's true. You said is sucks. Let me quote you: "Any dipole type antenna will suck on 75M if mounted less than about 100 feet, or about .4 wavelengths." That was in response to the original poster who said his antenna sucked, not me. It is still your statement. I posted the NUMBERS for an AVERAGE situation. And claimed the numbers as an absolute. I never made any such claim. snip remaining repetitive puerile drivel Your claim was that such antennas suck. Period. No qualifications. That is the definition of an absolute. But you're never wrong, are you? Even when presented with the facts. You just try to weasel out of it and/or ignore other applicable comments. Shows you for your true colors. All hot air but no understanding. -- ================== Remove the "x" from my email address Jerry, AI0K ================== |
#7
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It is a truism
Jerry Stuckle wrote:
On 11/14/2014 10:02 PM, wrote: Jerry Stuckle wrote: On 11/14/2014 4:26 PM, wrote: Jerry Stuckle wrote: On 11/14/2014 3:55 PM, wrote: Jerry Stuckle wrote: snip You ignore the fact this is an idealized environment. That is NEVER the case in a real installation. You ignore the fact this is modeled on an AVERAGE environment. But you claim it is an absolute fact that an 80 meter antenna at less than 100' is crap. This is solid proof. I never made any such claim nor did I say "an 80 meter antenna at less than 100' is crap". That's true. You said is sucks. Let me quote you: "Any dipole type antenna will suck on 75M if mounted less than about 100 feet, or about .4 wavelengths." That was in response to the original poster who said his antenna sucked, not me. It is still your statement. It was the posters statement and my response to that statement. snip remaining puerile drivel -- Jim Pennino |
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